From d090ec0df81e56556af3a2bf04a7e89347ae5784 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Thu, 31 Aug 2023 03:31:28 -0300 Subject: [PATCH] smp: Change function signatures to use call_single_data_t call_single_data_t is a size-aligned typedef of struct __call_single_data. This alignment is desirable in order to have smp_call_function*() avoid bouncing an extra cacheline in case of an unaligned csd, given this would hurt performance. Since the removal of struct request->csd in commit 660e802c76c8 ("blk-mq: use percpu csd to remote complete instead of per-rq csd") there are no current users of smp_call_function*() with unaligned csd. Change every 'struct __call_single_data' function parameter to 'call_single_data_t', so we have warnings if any new code tries to introduce an smp_call_function*() call with unaligned csd. Signed-off-by: Leonardo Bras Reviewed-by: Guo Ren Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230831063129.335425-1-leobras@redhat.com --- include/linux/smp.h | 2 +- include/trace/events/csd.h | 8 ++++---- kernel/smp.c | 26 +++++++++++++------------- kernel/up.c | 2 +- 4 files changed, 19 insertions(+), 19 deletions(-) diff --git a/include/linux/smp.h b/include/linux/smp.h index 91ea4a67f8ca..e87520dc2959 100644 --- a/include/linux/smp.h +++ b/include/linux/smp.h @@ -53,7 +53,7 @@ int smp_call_function_single(int cpuid, smp_call_func_t func, void *info, void on_each_cpu_cond_mask(smp_cond_func_t cond_func, smp_call_func_t func, void *info, bool wait, const struct cpumask *mask); -int smp_call_function_single_async(int cpu, struct __call_single_data *csd); +int smp_call_function_single_async(int cpu, call_single_data_t *csd); /* * Cpus stopping functions in panic. All have default weak definitions. diff --git a/include/trace/events/csd.h b/include/trace/events/csd.h index 67e9d01f80c2..58cc83b99c34 100644 --- a/include/trace/events/csd.h +++ b/include/trace/events/csd.h @@ -12,7 +12,7 @@ TRACE_EVENT(csd_queue_cpu, TP_PROTO(const unsigned int cpu, unsigned long callsite, smp_call_func_t func, - struct __call_single_data *csd), + call_single_data_t *csd), TP_ARGS(cpu, callsite, func, csd), @@ -39,7 +39,7 @@ TRACE_EVENT(csd_queue_cpu, */ DECLARE_EVENT_CLASS(csd_function, - TP_PROTO(smp_call_func_t func, struct __call_single_data *csd), + TP_PROTO(smp_call_func_t func, call_single_data_t *csd), TP_ARGS(func, csd), @@ -57,12 +57,12 @@ DECLARE_EVENT_CLASS(csd_function, ); DEFINE_EVENT(csd_function, csd_function_entry, - TP_PROTO(smp_call_func_t func, struct __call_single_data *csd), + TP_PROTO(smp_call_func_t func, call_single_data_t *csd), TP_ARGS(func, csd) ); DEFINE_EVENT(csd_function, csd_function_exit, - TP_PROTO(smp_call_func_t func, struct __call_single_data *csd), + TP_PROTO(smp_call_func_t func, call_single_data_t *csd), TP_ARGS(func, csd) ); diff --git a/kernel/smp.c b/kernel/smp.c index 385179dae360..822fabb7e3e1 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -125,7 +125,7 @@ send_call_function_ipi_mask(struct cpumask *mask) } static __always_inline void -csd_do_func(smp_call_func_t func, void *info, struct __call_single_data *csd) +csd_do_func(smp_call_func_t func, void *info, call_single_data_t *csd) { trace_csd_function_entry(func, csd); func(info); @@ -172,7 +172,7 @@ module_param(csd_lock_timeout, ulong, 0444); static atomic_t csd_bug_count = ATOMIC_INIT(0); /* Record current CSD work for current CPU, NULL to erase. */ -static void __csd_lock_record(struct __call_single_data *csd) +static void __csd_lock_record(call_single_data_t *csd) { if (!csd) { smp_mb(); /* NULL cur_csd after unlock. */ @@ -187,13 +187,13 @@ static void __csd_lock_record(struct __call_single_data *csd) /* Or before unlock, as the case may be. */ } -static __always_inline void csd_lock_record(struct __call_single_data *csd) +static __always_inline void csd_lock_record(call_single_data_t *csd) { if (static_branch_unlikely(&csdlock_debug_enabled)) __csd_lock_record(csd); } -static int csd_lock_wait_getcpu(struct __call_single_data *csd) +static int csd_lock_wait_getcpu(call_single_data_t *csd) { unsigned int csd_type; @@ -208,7 +208,7 @@ static int csd_lock_wait_getcpu(struct __call_single_data *csd) * the CSD_TYPE_SYNC/ASYNC types provide the destination CPU, * so waiting on other types gets much less information. */ -static bool csd_lock_wait_toolong(struct __call_single_data *csd, u64 ts0, u64 *ts1, int *bug_id) +static bool csd_lock_wait_toolong(call_single_data_t *csd, u64 ts0, u64 *ts1, int *bug_id) { int cpu = -1; int cpux; @@ -272,7 +272,7 @@ static bool csd_lock_wait_toolong(struct __call_single_data *csd, u64 ts0, u64 * * previous function call. For multi-cpu calls its even more interesting * as we'll have to ensure no other cpu is observing our csd. */ -static void __csd_lock_wait(struct __call_single_data *csd) +static void __csd_lock_wait(call_single_data_t *csd) { int bug_id = 0; u64 ts0, ts1; @@ -286,7 +286,7 @@ static void __csd_lock_wait(struct __call_single_data *csd) smp_acquire__after_ctrl_dep(); } -static __always_inline void csd_lock_wait(struct __call_single_data *csd) +static __always_inline void csd_lock_wait(call_single_data_t *csd) { if (static_branch_unlikely(&csdlock_debug_enabled)) { __csd_lock_wait(csd); @@ -296,17 +296,17 @@ static __always_inline void csd_lock_wait(struct __call_single_data *csd) smp_cond_load_acquire(&csd->node.u_flags, !(VAL & CSD_FLAG_LOCK)); } #else -static void csd_lock_record(struct __call_single_data *csd) +static void csd_lock_record(call_single_data_t *csd) { } -static __always_inline void csd_lock_wait(struct __call_single_data *csd) +static __always_inline void csd_lock_wait(call_single_data_t *csd) { smp_cond_load_acquire(&csd->node.u_flags, !(VAL & CSD_FLAG_LOCK)); } #endif -static __always_inline void csd_lock(struct __call_single_data *csd) +static __always_inline void csd_lock(call_single_data_t *csd) { csd_lock_wait(csd); csd->node.u_flags |= CSD_FLAG_LOCK; @@ -319,7 +319,7 @@ static __always_inline void csd_lock(struct __call_single_data *csd) smp_wmb(); } -static __always_inline void csd_unlock(struct __call_single_data *csd) +static __always_inline void csd_unlock(call_single_data_t *csd) { WARN_ON(!(csd->node.u_flags & CSD_FLAG_LOCK)); @@ -372,7 +372,7 @@ void __smp_call_single_queue(int cpu, struct llist_node *node) * for execution on the given CPU. data must already have * ->func, ->info, and ->flags set. */ -static int generic_exec_single(int cpu, struct __call_single_data *csd) +static int generic_exec_single(int cpu, call_single_data_t *csd) { if (cpu == smp_processor_id()) { smp_call_func_t func = csd->func; @@ -658,7 +658,7 @@ EXPORT_SYMBOL(smp_call_function_single); * * Return: %0 on success or negative errno value on error */ -int smp_call_function_single_async(int cpu, struct __call_single_data *csd) +int smp_call_function_single_async(int cpu, call_single_data_t *csd) { int err = 0; diff --git a/kernel/up.c b/kernel/up.c index a38b8b095251..df50828cc2f0 100644 --- a/kernel/up.c +++ b/kernel/up.c @@ -25,7 +25,7 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, } EXPORT_SYMBOL(smp_call_function_single); -int smp_call_function_single_async(int cpu, struct __call_single_data *csd) +int smp_call_function_single_async(int cpu, call_single_data_t *csd) { unsigned long flags;